[MaryOlson]

    I am interested in knowing!

    Thanks a millions in advance...

    Best Regards

[rajni]

    I am interested in knowing!

    Thanks a millions in advance...

    Best Regards

It's very simple, those links are followed by Search Engine is called Do-follow and those are not called No-follow.

[Gay]

 I'm not sure, but I think I saw this question already. If so, we have to put a link to that topic. I'll search it later...

[SEO]

  There are also some good explanations about DO-FOLLOW and NO-FOLLOW. Here you are: http://www.seo-forum-seo-luntan.com/seo/what-is-do-follow-and-no-follow/msg3760/#msg3760

[electra]

do follow links are those links on the websites which allows the flow of link juice where as nofollow links does not allow the passing of link juice.. better to go for dofollow links rather than nofollow links..

[appdeveloper]

Well, I think about that the google consider do follow link but not no follow.

[danibuggy]

DO-FOLLOW are the links which follow the search engine and NO_FOLLOW are those links which are not follow by search engine its highlighted by keyword .

[sam051]

Dofollow and nofollow both is a link category. Google follow only dofollow links and give response for it but nofollow links google never count but traffic comes through nofollow Google count and according to visitors Google give a rank for your website.

[websky19]

Do-follow is an search engine crawlers crawl the whole content on your webpage including images,links,keywords etc.Whenever they find a link,if the link is dofollow link then the crawlers follow the link and land on other webpage.

No-Follow links are ignored by search engine crawlers.Whenever you are linking to any website which is not of high value then use rel="nofollow" attribute in your html of the webpage. But it produces the traffic.

[jerrodmerit]

Dofollow refers to links that do not have nofollow attribute. It is recognized as a vote and the link will be crawled by the search engine spiders. If the link is dofollow, the page rank of the webpage can be transferred into your site.

[JimyBenvolio]

Well, this is repeated topic. 
Anyway, links which are crawled by the search engine are called do follow links and which not crawled are called no follow. Web master can set this option if he doesn't want to crawl links on his website.

[Julia Wells]

Dofollow link will make Google crawl to follow the link and index the page - Good for backlinks

Nofollow link will restrict your page from being crawled to your link.

[johnniewalk]

Dofollow is nothing but Indexing a Particular link and count as a quality backlink.
Nofollow link is indexed but not considered as a quality backlink from that website.

[bcetindra]

Nofollow links attributes do not allow search engine bots to follow link.That means if the website owner is linking back to you with nofollow attributes, it does not pass on link juice. Only Humans will be able to follow the links.

Dofollow links allow google (all search engines) to follow them and reach our website. Giving us link juice and a backlink.

[proka]

I actually dont do nofollow backlink building. Its pointless. You can share on facebook to get non follow if you want...